Genomic organization and expression profile of the mucin-associated surface protein (masp) family of the human pathogen Trypanosoma cruzi

Nucleic Acids Res. 2009 Jun;37(10):3407-17. doi: 10.1093/nar/gkp172. Epub 2009 Mar 31.

Abstract

A novel large multigene family was recently identified in the human pathogen Trypanosoma cruzi, causative agent of Chagas disease, and corresponds to approximately 6% of the parasite diploid genome. The predicted gene products, mucin-associated surface proteins (MASPs), are characterized by highly conserved N- and C-terminal domains and a strikingly variable and repetitive central region. We report here an analysis of the genomic organization and expression profile of masp genes. Masps are not randomly distributed throughout the genome but instead are clustered with genes encoding mucin and other surface protein families. Masp transcripts vary in size, are preferentially expressed during the trypomastigote stage and contain highly conserved 5' and 3' untranslated regions. A sequence analysis of a trypomastigote cDNA library reveals the expression of multiple masp variants with a bias towards a particular masp subgroup. Immunofluorescence assays using antibodies generated against a MASP peptide reveals that the expression of particular MASPs at the cell membrane is limited to subsets of the parasite population. Western blots of phosphatidylinositol-specific phospholipase C (PI-PLC)-treated parasites suggest that MASP may be GPI-anchored and shed into the medium culture, thus contributing to the large repertoire of parasite polypeptides that are exposed to the host immune system.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3' Flanking Region
  • 5' Flanking Region
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Conserved Sequence
  • Gene Expression Profiling
  • Genes, Protozoan
  • Genome, Protozoan
  • Membrane Proteins / chemistry
  • Membrane Proteins / genetics*
  • Membrane Proteins / metabolism
  • Molecular Sequence Data
  • Mucins / genetics
  • Multigene Family*
  • Protozoan Proteins / chemistry
  • Protozoan Proteins / genetics*
  • Protozoan Proteins / metabolism
  • RNA, Messenger / chemistry
  • RNA, Messenger / metabolism
  • Trypanosoma cruzi / genetics*
  • Trypanosoma cruzi / growth & development
  • Trypanosoma cruzi / metabolism

Substances

  • Membrane Proteins
  • Mucins
  • Protozoan Proteins
  • RNA, Messenger